Bestsellers are books that chart on bestseller lists and their rank depends on several different factors. In general, it is believed that because of language's universality, books originally written in English, have more potential readers. It's also surmised that books published by big publishing houses are more successful, and that male writers rule the bestseller lists. In the research of the actual influence of these factors on Amazon's bestseller lists in 2014 and 2017, I used the method of the author's impact factor and I systematically analyzed and compared the obtained data. Results showed that English is not crucial anymore for charting, and that most books are published by major publishing houses, while the share of self-published books is rising. In addition, the bestseller lists are ruled by female authors. The master thesis gives insight into the factors that actually influence the bestseller lists.